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We live in a rural area and can only get normal programming by satellite. So we use Direct TV, but we have a unique problem. For the house system, the antenna is located about 500 feet away because this the only place where we can get a low, southern shot, with the dish. This is antenna-to-base distance is beyond the reach of the DTV system using RG6/U cable.
As I understand it, what happens is that DTV applies a potential to the center wire of the coax, which then selects the required transducer [for the desired channel] at the antenna, according to the voltage. If there is too much of a voltage drop across the cable, then the transducer and channel selection are out of sinc, which causes a loss of signal. This had me stumped for a time as we could get some channels with a decent signal strenth, but others would not work at all.
I had this problem beat by retransmitting the signal from my office, which is much closer to the antenna. I found this nifty retransmitter developed for NASA that allows me to transmit the signal on CAT5. The video quality was excellent and everyone was happy. But, when we purchased a HD big screen TV for the house, we found that the retransmit system is vulenerable to ground differentials between my house and the office. This apparently has something to do with the scan rate of the TV. As a result, I have to keep my load in the office balanced or we get horizontal lines drifting upward on the screen. And best of all, if this happens, we can't change channels because the channel selection is broadcast from the house to my office and depends on the ground level! I assume that noise caused by the ground differential is the issue. We are also prevented from watching HD on the new TV except for on a few local stations that we get by regular antenna. But that is a minor issue: The load balancing business has to go. The people who designed the retransmitter have run out of options and ideas.
So, my only hope is to select a coax that would reduce the DC line loss by half, while still retaining the required characterestics needed for the signal transmission. I was going to start reviewing this to see if I could make everything match-up, but before I do, I wanted to throw this out to see if this approach is fundamentally flawed. Is there any reason why I can't simply upsize the cable size, match capacitance and inductance, or at least keep the impedance to a mininum, and expect this to work? This cable will cost something like $700, so I hate to just try it and see how it goes. Also, I'm not sure what frequencies DTV uses.
Any input is appreciated.
As I understand it, what happens is that DTV applies a potential to the center wire of the coax, which then selects the required transducer [for the desired channel] at the antenna, according to the voltage. If there is too much of a voltage drop across the cable, then the transducer and channel selection are out of sinc, which causes a loss of signal. This had me stumped for a time as we could get some channels with a decent signal strenth, but others would not work at all.
I had this problem beat by retransmitting the signal from my office, which is much closer to the antenna. I found this nifty retransmitter developed for NASA that allows me to transmit the signal on CAT5. The video quality was excellent and everyone was happy. But, when we purchased a HD big screen TV for the house, we found that the retransmit system is vulenerable to ground differentials between my house and the office. This apparently has something to do with the scan rate of the TV. As a result, I have to keep my load in the office balanced or we get horizontal lines drifting upward on the screen. And best of all, if this happens, we can't change channels because the channel selection is broadcast from the house to my office and depends on the ground level! I assume that noise caused by the ground differential is the issue. We are also prevented from watching HD on the new TV except for on a few local stations that we get by regular antenna. But that is a minor issue: The load balancing business has to go. The people who designed the retransmitter have run out of options and ideas.
So, my only hope is to select a coax that would reduce the DC line loss by half, while still retaining the required characterestics needed for the signal transmission. I was going to start reviewing this to see if I could make everything match-up, but before I do, I wanted to throw this out to see if this approach is fundamentally flawed. Is there any reason why I can't simply upsize the cable size, match capacitance and inductance, or at least keep the impedance to a mininum, and expect this to work? This cable will cost something like $700, so I hate to just try it and see how it goes. Also, I'm not sure what frequencies DTV uses.
Any input is appreciated.
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